h2 {
    text-align: center;
}

@keyframes flash {
    from {
        opacity: 1;
    }
    25% {
        opacity: 0;
    }
    70% {
        opacity: 0;
    }
    100% {
        opacity: 1;
    }
}

.c1 {
    margin: 50px auto;
    width: 100px;
    height: 100px;
    border-radius: 50%;
    /* border: 1px solid red; */
    position: relative;
}

.b1 {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background-color: #111;
    position: absolute;
    left: calc(50% - 10px);
    top: -10px;
    transform-origin: 10px 60px;
    animation: flash 2s infinite;
}

.b1:nth-child(2) {
    transform: rotate(45deg);
    animation-delay: -1.75s;
}

.b1:nth-child(3) {
    transform: rotate(90deg);
    animation-delay: -1.5s;
}

.b1:nth-child(4) {
    transform: rotate(135deg);
    animation-delay: -1.25s;
}

.b1:nth-child(5) {
    transform: rotate(180deg);
    animation-delay: -1s;
}

.b1:nth-child(6) {
    transform: rotate(225deg);
    animation-delay: -0.75s;
}

.b1:nth-child(7) {
    transform: rotate(270deg);
    animation-delay: -0.5s;
}

.b1:nth-child(8) {
    transform: rotate(315deg);
    animation-delay: -0.25s;
}


/* -----琴谱-------- */

@keyframes piano {
    from {
        transform: scaleY(1)
    }
    25% {
        transform: scaleY(1)
    }
    50% {
        transform: scaleY(3)
    }
    75% {
        transform: scaleY(1)
    }
    to {
        transform: scaleY(1)
    }
}

div.c2 {
    margin: 0 auto;
    width: 200px;
    height: 100px;
    /* border: 1px solid black; */
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.b2 {
    height: 40px;
    width: 20px;
    background-color: black;
    animation: piano 0.6s ease-in-out infinite;
}

.b2:nth-child(2) {
    animation-delay: -0.5s;
}

.b2:nth-child(3) {
    animation-delay: -0.4s;
}

.b2:nth-child(4) {
    animation-delay: -0.3s;
}

.b2:nth-child(5) {
    animation-delay: -0.2s;
}

.b2:nth-child(6) {
    animation-delay: -0.1s;
}


/* 翻转Loading */

@keyframes flip {
    25% {
        transform: rotateX(180deg)
    }
    50% {
        transform: rotateX(180deg) rotateY(180deg)
    }
    75% {
        transform: rotateX(360deg) rotateY(180deg)
    }
    100% {
        transform: rotateX(360deg) rotateY(360deg)
    }
}

@keyframes flip1 {
    0% {
        transform: perspective(140px) rotateX(0deg) rotateY(0deg);
    }
    50% {
        transform: perspective(140px) rotateX(-180.1deg) rotateY(0deg);
    }
    100% {
        transform: perspective(140px) rotateX(-180deg) rotateY(-179.9deg);
    }
}

.b3 {
    margin: 0 auto;
    width: 100px;
    height: 100px;
    background-color: #111;
    animation: flip1 1s linear infinite;
    /* transform: perspective(0) rotateY(30deg) */
}


/* 圆形放大Loading */

@keyframes smaller {
    from {
        transform: scale(1);
        background-color: rgb(109, 109, 109);
    }
    50% {
        transform: scale(0);
        background-color: rgb(0, 0, 0);
    }
    100% {
        transform: scale(1);
        background-color: rgb(109, 109, 109);
    }
}

.c4 {
    margin: 0 auto;
    width: 100px;
    height: 100px;
    /* border: 1px solid black; */
    position: relative;
}

.b4 {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    position: absolute;
    opacity: 0.6;
    background-color: rgb(139, 139, 139);
    animation: smaller 2s linear infinite;
}

.b4:nth-child(2) {
    animation-delay: 1s;
}